> It looks decidedly odd in its own include file as you've done it. Wouldn't> the right way to do this be to split it into its own .c file and conditionally> compile it in the Makefile?

It will soon have lots of company, as this is where the pluginsfor CONFIG_TINY_PREEMPT_RCU will go. In other words, kernel/rcutiny.cwill have the same relationship to kernel/rcutiny_plugin.h thatkernel/rcutree.c has with kernel/rcutree_plugin.h.